Knife sharpening machine



June 7, 1938.

W. B, HAUSMAN 'KNIFE SHARPENING MACHINE Filed April 9, 1936' 3 Sheets-Sheet l l'uJerzZon June 7, 1938.

w. B. HAUSMAN KNIFE SHARPENING MACHINE Filed April 9, 195e :s sheets-sheet 2 lder-E11 Wrd qusnzarg June 7, 1938. W B. HAUSMAN 2,120,096

'KNIFE SHARPENING MACHINE Filed April 9, 1956 3 Sheets-Sheet 3 CFI y the ratchet mechanism in a manner that it may Patented June 7, 1938 v UNITED YSTATES ATENT OFFICEr i 2,120,096 KNIFE sHAaPENlNG MACHINE Ward B. Hausman, Philadelphia, Pa.

Application April 9, 1936, Serial No. 73,432

5 Claims.

My invention relates to a new and useful knife sharpening machine and more particularly to a machine for grinding serrated knives such as used in gangs or banks in bread slicing machine where entire loaves of bread are sliced at one operation.

An object of the invention is to produce a machine of this character which is semi-automatic in operation and capable of accomplishing accurate work.

Another object of the invention is to provide Fig. 2 is a top plan View thereof. 10 means for positively grinding a certain complete Fig. 3 is a fragmentary view of the rack bar area of a serrated knife, for example7 the mateand ratchet with the latter in its operative posirial bordering a V-shaped notch7 each time a tion. cut or grinding operation is made. Fig. 4 is a fragmentary detail View of the lat- Another object of the invention is to provide a eraliy adjusting means for the grinding wheel 15 clamp for a knife having spring means to urge frame. the knife outward until the adjustment is com- Fig. 5 is an end View of the machine. pleted. n i i Fig. 6 is a section on the line 6-6 of Fig. 1

Another object of the invention is to provide without the driving means. n i a gauge on the clamp which will set the cutting Fig. I is an enlarged detail of the cam and oscil- 20 edge of the knife properly relative to the grinding lating bar. Wheel regardless of the width'of such knife. I Y Fig. 8 is a fragmentary detail view of the knife Another object of the invention is to provide clamp, the oscillating bar to reciprocate said mechanism for moving the` clamp and component clamp, the operating cam and the grinding wheel, n parts endwise intermittently or step by step a illustrating their relations when inoperative po- 25 distance equal to the spacing of the serrations sitions. whereby one side of two adjacent serrations will Fig. 9 is an enlarged `rear View of the knife be ground simultaneously. clamp, and

Another object of the invention is to make a Fig. 10 is also a rear view with the back plate rack bar of unique construction for use in conor jaw removed and showing how a knife is set 3o therein and position-ed by the gauge which is illustrated in dotted lines. i In carrying out my invention as herein embodied, I5 represents a base plate of the main fram-e I6 to be mounted on a table, bench orV 35 other suitable supporting means, not shown. At both ends are standards I I carrying bearings I8 in which the rack bar I9 is slidably and rotatably mounted.

nection with the Vintermittent clamp` moving mechanism.

Another object o-f the invention is toV construct be thrown out of operation and the disengaging of the ratchet from the rack bar will move the actuating lever out of the pathV of -travel of the knocker pin. f

Another object of the invention is to mount the grinding Wheel on a frame capable of for- 'I'his rack bar I9 has a rack 20 only on oneend 45 t ward and backward as well as lateral adjustment DYOduCed 1n Splfal 01" threadformatlron- I haVe to take un fonwe'ai. on the g1inding Wheel and discovered that when a rack 1s made on one side setting said Wheel relative to the serrations of the of' a bar the latter W11; bow or become m15' knife shaped whereas by forming the cutsrall around A further object of this invention is to provide glatgdl; feeglgcgstlef leolce 45 meansdforfdssmg hlgindmg vhelrwnch Wu is that whenever it becomes worn along one line berea ,y or use a a unes an W 1C can e it may be turned slightlyv and a new surface is adjusted for wear. i presented Y A still further object of the present invention The rank bai. |9 isi'noved longitudinally sten by 501' is to construct a compact devlce of the kind menstep Oi intermittently through the medium of a tioned which iS Capable 0f ODEIaOH by` PGISOUS ratchet or pawl 2l mounted von an axle 22 jourother than highly skilled artisans. nalled in a yoke 23 at the upper end'of the ratch- With the above and other objects in view this et operating lever y24 pivoted intermediate its invention consists of the ldetails of construction ends, as at 25. The lower end of said lever 24 is 55.'

- Y hayi-ng -a bevel gear 32 thereon, `meshing with a urged outward, preferably by a spring 26, and is forced against the action of said spring by a knocker pin 2 on the .revolving shaft 28. Y protruding end of the axle is a weight 29Vwhich,

when swungrto one sideof the vertical center of Y the axler22, positions the pawl 2l inoperative relation to the rack 20, Fig. 3, and, when swung over to the other side, holdsrsaid pawl out of engagementv with said rack, Fig. 1.

disengaged from the rack, aV lug 30 isV pro-vided Vand preferably formed on the hub of said pawl Aso as to co-act withthe machine frame, for exam'-V ple, one of the standards Il, and force the upper endof the pawl operating lever 2,4,outward Where bythe lower end of said Vlever is'm'ov'ed inward against the action of the spr-ing 125. Th-eV inward throw of'the pawl is limited byran adjusting screw 3i threaded through themachine frame, or

' l one of its standards H, and positioned to be en- .e shaft gaged by the upper part of the pawl operating` lever-24 ner and for purposes of illustration :it is 4shown as bevel vgear Y33 ron ,ai countershaft .34 driven from l ai motor -35-,through reduction gears Yin the gear jaw. `Ml, .is fastened. .al-'resilient knife lifterV or Y A pusher 44,.Fig. 1'0, preferably formed from a sec-"- tion. of spring wire fashioned into practically Vf shape with its endsy bent at right angles to .provide anyordinary opening movement of the jaws. As saidv restsextend. lacross the openlngor space fbdx'as. YThis Shaft 2a may be additionally sup- 3o ported intermediate its ends by an adjustable standard M -Aiknife-clamp Y38 is xed to the rack bar I9 vby'earsY 39 formed with the front jaw E of said;

clamp, and .a rear Yjaw 4|A lis mounted 1in. place Y by adjustable fasteningV means herein illustrated `as including screws 42 and wing nuts '43.'4 ToV the inner face of` oneofthe jaws, as the front knife Arests 45 of sufficient length to'accommodate .between'the .jaws awaymust -be provided to take care of said rests wherefore elongated oblique apertures -461are produced -in theother jaw, as the Y Yrearfjaw 4l,Y throughY or into which saidrests project, Fig.9.v Y i.. 'With-the jaws of thefclampf38 open aknife 41,

having aserrated cutting edge 48, is inserted and' forced inward'againstthe action ofthe resilient I provide'a'gauge 49 consisting of a plate 50 at tache'd to the ends of "a .frame '51, 4Vpreferably U-..

lifter 44 untilsaid knife is properly positioned atV which time the jaws are clamped on the knife by the Wingnuts. In Yorder to set the serrated cutting edge'of the knife in the proper'position regardlessjoffthe widthorV depth of said knife,

shaped,.hinged or 'swinginglyconnected at 521to the 'clamp `and moreV particularly 'to the front. jaw thereof. YfI'his gaugehas a'fixed relation to the clamp s o'that by placing a knife in said Yclamp andfthenj swinging the gauge'overaboveY the cut..

ting edgefthe latter. will.. be lifted or pushed against thet'gauge plate ,by4 the lifter 44, after which the'clamp may 'beclosed ontheikliife.

In addition to'theclamp being moved longitu-v dinally with the rackbar, said clamp to be recip/rocated.

i ment afrocker'arm 5`3isffjired tothe rack bar,|9

1 and lhasa vlever cam 54Y pivoted within lan aperv l ture in the rocker arm-and co-acting with a'shoe v 55.j-pivotef;1tov the upper/portion of said rocker arm V,as -at '56.: .'Ihefreefendr of the shoe `55 is urged toward said rocker arm 53 by a leaf spring Orl a.

In orderY t0Y move theoperating .lever 24 out of the .path of travel ofthe knocker pin 21, when the pawl is` 28d-s revolved inrany suitable manl To accomplishl this last'move- 51 xed to the hub of ,the rocker arm andv bearing against the shoe, Fig. 6, and at the same time the rocker arm is urged inward bythe weight 58 connected to the'rack bar I9 andfso rotating the latter in onedirection.

Torotate said rack bar Vin the Vopposite direc-V tion and thus reciprocate the knife clamp and component'partsI provide a cam wheel 59 hav Y' VV. f

ing an eccentric surface vand a ilatisurface 6I so therewill be a gradual rise and a sharp drop. This cam is mountedon'theshaft 28 Vand co-acts vritha bar 52 carried bythe brackets 63 pivoted Y at "64 to suitableparts of ther machine frame and the face y'of said bar opposite that acted upon by. the cam isV engaged by the shoe 55 of the clamp Y reciprocating mechanism. The knocker pin Y2'1 and the flat surface V6| of the cam 59 are solocated relative to eachother, or timed, that while said flat camV surface isfcontiguousthe bar 62,Y

the knocker'pin 2l engages and .actuatesrrthe lever 24 of the pawl 27|.Y

With the parts .as .in Fig. 5the clamp 38 has been retracted and .a knife can be removed from or placed in saidV clamp as the" case may be.v The handle of the lever cam 54 is then'swung down as ing-Fig. 6. This will positively .force the shoe 55 against the bar (i2-and swing the rocker arm 53 outward thus rotating the rack -,-bar and 'moving the upper edge of the clampV 38 inward.

Then as `the', cam wheel 5'9 revolves itwill graduallvmove the shoe 55, the rocker armV 53 and A V'component parts 'outward and the upper edge of the clamp 38 fartherjinward.' During vthis step of the operation, the drag foot `65 onthe rocker armj53 willbe forced against the drag bar. 66

the'roc'ker karm 53, rack` Vbarfl9',a clamp 38 and component parts.` As Ysoon as theflat surface 6| of thecam5`9 reachesthe bar 62, the latter will move'inward along with rocker arm 5,3., due to andprevent accidental longitudinal movement'o'f.

the action of` the weight 58. This will 'retractA thecl'ampSB and release the drag foot iwhereupon the pawl 2| will be actuated tomovethe` rack Vbar I9 longitudinally one step. j

. Another pair ofV standards 61'v are provided,

which forl purposefof. claritywill be termedsup-` plemental fstandardsyand in these is rotatably and'.

slidably mounted va shaft6'8fj" krI-his"shaft isjurgecl longitudinall'y in one direction by a spring .69,

Fig. 4,' socketed in Yofnef Athe supplemental standards andengaging a collar on said shaft@k The shaft 68V is moved longitudinally inthe l'ope positeV-direotion loyfa lever 1Upivoted interme` i diate its ends at 1| with enel-end in cont'act'with the v'shaft and the other end having a screw 12 Y threaded through lit' and impingingonja portion of one of the supplementaryY standards Yfl'l where-Y Vby the shaft 68 may be Vadjusted,any* desired'small amount. Y

on theY lshaft 'rss is fixedja swinging:'frrdrne'1'3VV havingbearingsY at theupper end for the. :grind-f' r' ingvwheelgs-haft 14 carryingfa grinding wheel? Y` 15mm its perimeter-fashioned toerind vfshapedf serrations on `the, knife.

journa-lled onja trunnion carriedbythefree end of the arm -B-l which has its'in'ner on one vof the vsuppleinental ls'tanda-rds 61. Y Y h YThe, upper v end of Vthe swinging. vframe 13 Yis Vurgingrearwardly or outwardly by a spring' 76| having one fend-'anchored to .abrac'ket 182 mounted Thegrinding Wheel.

on the machine frame, as one of the supplemental standards 5l', and the other end attached to a suitable part of said swinging frame. The lower end of the swinging frame 13 istherefore urged forwardly or inwardly and is engaged by a screw 83 threaded through a boss 84- on the frame. By screwing the screw 83 inward the grinding wheel 'I5 will be moved toward the vknife inthe clamp 38 so that wear on saidV grinding wheel may be compensated for or a-deeper cut made in the knife and by `backing out the screw 83 the spring 8| will draw the grinding wheel away from the knife and relieve the pressure or make a shallower cut. This will also permit the installation of a new or larger diameter grinding wheel.

From this it will be apparent that the provision of the swinging frame makes it possible toadjust the grinding wheel lateral relative to the knife serrations, if the knife is-not accurately positioned in the. clamp, and also to and-fro'if the knife is not properly meeting said grinding wheel.

In order to occasionally dress the perimeterof the grindng wheel to maintain the proper bevels thereon, I provide a bracket 85 attached to the swinging frame 13,with guide arms ,86 adjustably mounted thereon to be set at angles corresponding to the inclination of the grinding wheel bevels. On these guide arms are slidably mounted holders 8l in which the dressing tools 88 are screw threaded. When the arms are properly adjusted and the working ends of the tools projected from their holders sufficiently to contact the perimeter of the grinding wheel, said holders may be slid along their respective guide arms and both bevels of the grinding wheel will be dressed or cleaned and reshaped.

The operation is as follows:-.

To set the machine, the pawl or ratchet 2| is thrown out of engagement with the rack bar I9 which will move the ratchet operating lever 24 out of the path of travel of the knocker pin 21. This will permit the operator to manually slide the rack bar longitudinally, toward the left in Fig. 1, until said rack bar is in a starting position. The lever cam 54 is also released by throwing its handle upward to cause the rocker arm 53 to approach the shoe 55 which will retract the knife clamp 38 due to the action of the weight 58. Next said clamp is opened and a knife inserted so that the serrations at the forward end of said knife are properly positioned relative to the grinding wheel 'l5 or approximately so. The gauge 49 is swung over the cutting edge of the knife and the resilient pusher 44 will force said knife against the gauge. This brings the cutting edge to a predetermined location for engaging the grinding wheel when the knife clamp is reciprocated regardless of the width of the knife. 'Ihe clamp is now closed or tightened on the knife and the gauge swung back away from the knife.

Upon the knife being fastened in theclamp, the ratchet pawl 2| is placed in operative position as shown in Fig. 3, and the handle of the lever cam 54 is turned down as in Fig. 6. TheV revolving of the shaft 28 will cause the bar B2 to be quickly forced outwardly a distance sufficient to cause the knife Vto engage the grinding wheel and then gradually add pressure on the knife to bar a distance equal jto the Vspacing Tof 'the' serrations on rthe knife so when the-knife isagain moved ytoward .the grinding wheel a different surface will lbe ground.. VIf the serrations are improperly engaging the grinding vwheel, the? screw 12, Fig; 4, is moved in or out therebyadjusting the grinding wheel laterally until proper alignment is obtained Vand if the grinding cut is not deep, enough or is deeper than desired, the screw 83 is screwed in the proper direction toadjust the grinding wheel relativeY to the` work by. the to and fro movement of the swinging frame 13. "After the parts are properly adjusted'the machine continues to move the rack barlongitudinally stepby stepand intermittently reciprocate the same so that all 'of the serrations-will be ground to a sharp cutting edge. @Particular of course I do not wish to ne limited to the exact details of construction herein shown andk described as these may be Varied withinV the scope of the appended claims without departing from thespirit of my invention. l

Having thus described my invention what l claim as new and useful is:--A` N 1. In combination, a machine frame including a pair of supplementary standards, a shaft rotatably and slidably mounted on said supplementary standards, a grinding wheel supporting frame fixed to said shaft, means coacting withthe grinding wheel supporting frame to oscillate the latter, means to urge said shaft longitudinally in one direction, means to move said shaft in the opposite direction whereby the -grinding wheel wheel supporting frame, means to drive said,

grinding wheel shaft, a grinding wheel mounted on the last named shaft and having a V-shaped perimeter, a knife holding means adjacent the grinding wheel, means to intermittently move said knife holding means crosswise of the grinding wheel, and means to reciprocate said knife holding means.

2. In a knife sharpening machine, a machine frame including a pair of primary-standards and a pair of supplementary standards to the rear of said primary standards, a grinding wheel supporting frame mounted on the supplementary standards and capable of lateral and to and fro adjustments, a grinding wheelon a shaft journalled in the grinding wheel supporting frame, a rack bar slidably and rotatably mounted on the primary standards, a knife clamp Xed to said rack bar adjacent the grinding wheel, a rocker arm fixed to said rack bar, means to move saidl clamp, and a ratchet pawl to move the rack bar and the clamp endwise.

3. In a knife sharpening machine, a machine frame, a grinding wheel mounted 0n said frame. a rack bar slidably and rotatably mounted on said frame, a knife clamp fixed to the rack bar adjacent the grinding wheel and movable with said rack bar, a rocker arm also xed to and movable with the rack bar, a shoe pivoted at itsV upper end to said rocker arm, means to move said shoe and rocker arm apart for swinging the clamp inward, means to urge the free end of the shoe toward the rocker arm, a weight connected with the rack bar to rotate the latter in one limited inward movement and a slow furtherY in? Vward lmovementV and a quick return movement,

a ratchet pawl co-acting with the rack bar to intermittently slide said rack bar longitudinally, Y an roperating leverfor saidvpawl, and aknocker pin on the camshaft to engage said lever and actuate the'pawl while the flat of the cam is in engagement with itsV co-acting bar.

4. 'I'he 'structure in claim 3,'in combination Withca drag foot carried bythe rocker arm, and a drag bar with which said foot co-acts to prevent accidental longitudinal movement of the rack bar and component parts. K

5. In a knife sharpening machine, a machine frame, a grinding wheelmounted on said frame, a rack bar slidably' and rotatably mounted on Y said frame andv having a spiral rack on one end,

a cam shaft journalled on said frame, a cam to theframe, said barco-acting with said cam and'moved in one direction by the latter, means f fixed to the rack bar and coacting with the cam actuated bar'to rotate the rack bar in one direction, a weight attached to said ,rack bar for ro'- tating the rack* bar inthe opposite direction; a

ratchet lever pivoted intermediate its ends on the machineframe, `means to urge the lower end outward,'means adjustablyv mounted on the 1na xedtothe cams'haftga bar having legspiv'oted 'n chine frame to limit the inward movement Aof J Y the upper end of saidrratchet lever, a ratchet pawl pivoted to said upper end of the lever and adapted to be moved into or out of engagement with the rack, a' lug on said pawl to contact the machine frame and hold the upper end of the lever outward and thelower end thereof inward, a -weight to maintain the pawl in itsOperative or inoperative positions, a knocker pin onY the cam shaft to actuatethe ratchet lever at regular intervals for intermittently moving the rack bar, longitudinally, and a knife clamp on the rack bar adjacent the Ygrinding'wheel to be reciprocated by the` rotations of the rack bar and moved crosswise of the grinding wheel "by the longitudinal movements of said rack bar.

WARD B. HAUSMAN. 

